package cn.lanqiao.common.identifyingCode;

import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.util.Arrays;
import java.util.Random;

public class HeightCode
{
  public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
  private static Random random = new Random();
  
  public static String generateVerifyCode(int verifySize)
  {
    return generateVerifyCode(verifySize, "23456789ABCDEFGHJKLMNPQRSTUVWXYZ");
  }
  
  public static String generateVerifyCode(int verifySize, String sources)
  {
    if ((sources == null) || (sources.length() == 0)) {
      sources = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
    }
    int codesLen = sources.length();
    Random rand = new Random(System.currentTimeMillis());
    StringBuilder verifyCode = new StringBuilder(verifySize);
    for (int i = 0; i < verifySize; i++) {
      verifyCode.append(sources.charAt(rand.nextInt(codesLen - 1)));
    }
    return verifyCode.toString();
  }
  
  public static BufferedImage getBufferedImage(int h, int w, String code)
  {
    int verifySize = code.length();
    BufferedImage image = new BufferedImage(w, h, 1);
    Random rand = new Random();
    Graphics2D g2 = image.createGraphics();
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
    Color[] colors = new Color[5];
    Color[] colorSpaces = { Color.WHITE, Color.CYAN, 
      Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE, 
      Color.PINK, Color.YELLOW };
    float[] fractions = new float[colors.length];
    for (int i = 0; i < colors.length; i++)
    {
      colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
      fractions[i] = rand.nextFloat();
    }
    Arrays.sort(fractions);
    
    g2.setColor(Color.GRAY);
    g2.fillRect(0, 0, w, h);
    
    Color c = getRandColor(200, 250);
    
    g2.setColor(c);
    g2.fillRect(0, 2, w, h - 4);
    

    Random random = new Random();
    
    g2.setColor(getRandColor(160, 200));
    int count = 20;
    for (int i = 0; i < count; i++)
    {
      int x = random.nextInt(w - 1);
      int y = random.nextInt(h - 1);
      int xl = random.nextInt(6) + 1;
      int yl = random.nextInt(12) + 1;
      g2.drawLine(x, y, x + xl + 40, y + yl + 20);
    }
    float yawpRate = 0.2F;
    int area = (int)(yawpRate * w * h);
    for (int i = 0; i < area; i++)
    {
      int x = random.nextInt(w);
      int y = random.nextInt(h);
      int rgb = getRandomIntColor();
      image.setRGB(x, y, rgb);
    }
    shear(g2, w, h, c);
    
    g2.setColor(getRandColor(100, 160));
    int fontSize = h - 4;
    Font font = new Font("Lucida Sans", 2, fontSize);
    g2.setFont(font);
    char[] chars = code.toCharArray();
    for (int i = 0; i < verifySize; i++)
    {
      AffineTransform affine = new AffineTransform();
      affine.setToRotation(0.8975979010256552D * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), w / verifySize * i + fontSize / 2, h / 2);
      g2.setTransform(affine);
      g2.drawChars(chars, i, 1, (w - rand.nextInt(10)) / verifySize * i + 5, h / 2 + fontSize / 2 - rand.nextInt(10));
    }
    g2.dispose();
    return image;
  }
  
  private static Color getRandColor(int fc, int bc)
  {
    int count = 255;
    if (fc > count) {
      fc = count;
    }
    if (bc > count) {
      bc = count;
    }
    int r = fc + random.nextInt(bc - fc);
    int g = fc + random.nextInt(bc - fc);
    int b = fc + random.nextInt(bc - fc);
    return new Color(r, g, b);
  }
  
  private static int getRandomIntColor()
  {
    int[] rgb = getRandomRgb();
    int color = 0;
    int[] arrayOfInt1 = rgb;int j = rgb.length;
    for (int i = 0; i < j; i++)
    {
      int c = arrayOfInt1[i];
      color <<= 8;
      color |= c;
    }
    return color;
  }
  
  private static int[] getRandomRgb()
  {
    int count = 3;
    int[] rgb = new int[count];
    for (int i = 0; i < count; i++) {
      rgb[i] = random.nextInt(255);
    }
    return rgb;
  }
  
  private static void shear(Graphics g, int w1, int h1, Color color)
  {
    shearX(g, w1, h1, color);
    shearY(g, w1, h1, color);
  }
  
  private static void shearX(Graphics g, int w1, int h1, Color color)
  {
    int period = random.nextInt(1)+1;
    
    boolean borderGap = true;
    int frames = 1;
    int phase = random.nextInt(1)+1;
    for (int i = 0; i < h1; i++)
    {
      double d = (period >> 1) * 
        Math.sin(i / period + 
        6.283185307179586D * phase / 
        frames);
      g.copyArea(0, i, w1, 1, (int)d, 0);
      if (borderGap)
      {
        g.setColor(color);
        g.drawLine((int)d, i, 0, i);
        g.drawLine((int)d + w1, i, w1, i);
      }
    }
  }
  
  private static void shearY(Graphics g, int w1, int h1, Color color)
  {
    int period = random.nextInt(40) + 10;
    
    boolean borderGap = true;
    int frames = 20;
    int phase = 7;
    for (int i = 0; i < w1; i++)
    {
      double d = (period >> 1) * 
        Math.sin(i / period + 
        6.283185307179586D * phase / 
        frames);
      g.copyArea(i, 0, 1, h1, 0, (int)d);
      if (borderGap)
      {
        g.setColor(color);
        g.drawLine(i, (int)d, i, 0);
        g.drawLine(i, (int)d + h1, i, h1);
      }
    }
  }
}
